Speed-indicator.



110. 815,708.l PATBNTBD MAR. 20, 1906. 0.111115.- l

, SPEED INDICATOR. APPLIOATIONHLBD 11u13. 1905. K

' a SHEETS-SHEET 1.

v No.V 815;'108."

y IHLE. y v SPEED INDICATOR. APPLIO'ATION FILED MAY 13, V1905.

' PATENT-ED MAR. 29,1906.

- 3 SHEETS-SHEET 2.

of 4 Alexandrinenstrasse, Berlin, have .invented certain new and usefulImniw ITED sTATEs PATENT oEEIoE.

GIIsIu/ivA inLE, OEBERLIN, GERMANY, AssIGNoR To MAX STEINBERG, E,cHARLorrENBUEG, kNEA-E BERLIN, GERMANY, `AND MAx TRIrTEaoE BERLIN,GERMANY.

To all tail/0m it may concer-n: I Be it known that I, GUsTAv IHLE,engineer, Germany,

proveme'ntsin Speed Indicators, of which "the following is aspecification.

The'present invention .has for its ob'ect an limprovellfent'.in speedindicators wit -magnets and indicating members rotating around` the sameaxis.

In -accorc'lance -with 'the invention Vthe ,I

dicating member, which is connected'in -the Zaortance for obtaining a nvanta dicating member is` situated in usual manner" with the indicatingmechan ism, consists of a hollow body and is inclosed upon kthe greaterpart of'itsperipheryby the rotated` magnet system, an iron core whichrotates'with the system of magnets extend- .ing into this, hollowindicatmg member.

Owing' to lthis arrangement, itis ypossible to emplo a system of magnetsforming a conlow indicating member may be of exceedingly small mass. Theemployment of a system ofmagnets of large mass is `of great im-v owerfulmagneticV as the hollow ina specially EOWerful magnetic field lits ma'ssmay vbe l ept ,comparatively smalland yetthe rotary fie d-generatedbythe eddy-currents flowing through itmay be powerful. vA furtheradvantage consists in the -fact that the-light hollenT indicatingmemberpwhich' may ad-- veously bemade of aluminium, is readeld. .-On theother han tions of velocity, as the bearing friction is ex- "trem lysmall 1n view-of the small mass of 'A presents the advantage that themagnet-ici the o'tary body. By this means, therefore,. the exactness Vofvthe `indications is largelyA increased. The novel arrangement likewisecircuit-is'almost completely closed andthe 'entire' periphery or almostthe entire periphery offthe hollow indicating-'liody is effect- -ivelyacteld'upon bythe magnetic lines of force Owing-to the'- provision ofAthe iron core lilling 'the hollow indicating body, the

air resistance is decreased and a. magnetic field of greater ldensity isobtained, and this results 1n eating. 4

-Constructional forms 'of the novel speed-s Speccationpf Letters Patent,l Application ned my 13, 1906. serial No. 260.305.

great sensitiveness the indi-.

tem in the 'field o of .lines of force.

,mis provided with an mdex p, whichA passes SPEED-INDICATQR.

Patented Mareny 2o, 1906.

indicator are illustrated, by way of example,

in the accompanying drawings, in 'which- Figures 1 to 4 illustrate oneconstruction al form of thisvs eed-indicator. Fig. 1 is a sideelevation. 2 is a front Selevation looking at the scale.- Fig. 3. isyarear elevation looking. at the system of magnets.-v Fig. 4 is a planview in horizontal section. Figs. 5

and '6' illustrate another constructional form.

Fig; 5 is a side elevation of the system of mag- -The aluminiumbody cismounted upon a I spindle e which is rotatable, and upon one of ssv netswithout Athe casing, and'Fig. 6 isavsec'- tional plan.

t Thel speed-indicator in accordance .with

Figs 11to'4 consists of a system of magnets its endsa spiral spring fisfixed, its other extremity bemg arranged in the casing. Now

if the system of magnets is rotated eddy.- currents are set up in thealuminium body c.l

Owing to the mutual reactions of the system of ma nets 'and of thealuminium bod?7 traversed y eddy-currents this latterwil tated untilequilibrium is established, with the force of the spring f opposing thisrotation.

The speed obtalmn for the time being may be readby means o the index andscale. In the constructional f ormillustrated in Figs. 5 and 6l `thehorseshoe-magnets g, ,to

core 'L' connected with the magnets, constitute a system ofmagnets-which by means of the hollow trunnions 7c, the `velocityof which getherwith their pole-pieces h h and t e lron" be roiently bedriven-'b'y`means of a cord which is passed around one ofr the trunnionsc, formed as jacord-pulley kf, and around the shaft the velocit of whichis to be determined. Upon a spin le m, passing freely throughl thetrun-v niqns k, the lndl'catm member 1L,- `Which is formed as acylindrical ollow body, is mounted; in such a manner that it rotates.concen- IOO trically between the pole-pieces -h hand the I Iron core t,connected with the' magnetic sys- The shaft l other extremity ofthesprin g is attached at 1 to 'a special arm s, mounte upon the stand l,and in this arm, in combination with a second arm t, the spindle m ismounted in such a manner that it 1s impossible for the indicat-'ing-bodyl rnJ to be displaced by Jfriction.

The tails of the invention may of course be modified. isespeciall thecase with 'reference tothe mounting of tie hollow indicating member, forvwhich bearings may be provided upon one or upon both-sides.

The indicating-body may be constructed of any appropriate metal. In thepresent case aluminium has been selected in order to keep the wei ht ofthe indicating-body as small as possi le. An essential point is that inall cases thel indicating member consti* tuted byy a hollow body shouldbe inclosed on the greater part of its periphery by the rotate system ofmagnets and that an iron core rotating with the system of magnets shouldextend within the hollow body.

Having now particularly described and ascertained the ynature of my saidinvention and in what manner the same is to be performed, I declare thatwhat I claim isl. In a speed-indicator, the combination of magnetsmounted upon trunnions, means for rotating said magnets upon said trun'#nions, an-armature disposed within the field of said magnets, andindicating mechanism connected with said armature.

2. In a speedfind'icator, the combination of magnets mounted upontrunnions vand pro'- vided with pole-pieces, an armature disposedintermediate of said pole-pieces and adapted to have eddy-currents setup therein, a spindle connected with said armature for supporting thesame, said spindle-extending through said trunnions of saidfmagnets,bearings for supporting said spindle, indicating mechanism connectedwith said spindle, and means for rotating said magnets.

3. In a speed-indicator, the combination of an indicating memberrotating around an axis, magnets free to rotate around the same axis,said3 magnets producing a field, a hollow metallic member mounted withinsaid field and connected with said indicating member, said hollowmetallic member being inclosed for the greater part of its periphery bysaid ma nets, and an iron core extending into sai hollow metallic memberfor the purpose of facilitating the formation of eddy-currents therein.

4. In aspeed-indicator, the combination of magnets provided with meanswhereby they may be rotated, said magnets producing a field a hollowmetallic member disposed within said field and inclosed for the greaterpart'of its periphery by the poles of the magnets, trunnions forsupporting said magnets, said trunnions being provided with axialpassages, Vand a 'spindle revolubly mounted within said axial passagesand connected with said hollow metallic member for supporting the same.

5. In a speed-indicator, the combination of means for producing amagnetic' field, a magnetic member mounted within said magnetic fieldand coacting therewith for the purpose of increasing thema netic flux, aho low member and disposed within said magnetic field, bearings forenabling said hollow metallic member to rotate, and an 1nd1cat1ng-neeGUSTAV IHLE.

Witnesses WOLDEMAR HAUPT, HENRY HASPER.4

metallic memberl encirc ing said magnetic' dle connected with saidmember for exhibit-

